How severe is CVE-2001-0666?

CVE-2001-0666 has a CVSS 2.0 base score of 2.1, rated low severity.

Is CVE-2001-0666 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2001-0666?

CVE-2001-0666 affects Microsoft Exchange Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2001-0666?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2001-0666 published?

CVE-2001-0666 was published on 2001-10-30 and last updated on 2026-06-16.

CVE-2001-0666

CVE-2001-0666 is a low-severity vulnerability in Microsoft Exchange Server with a CVSS 2.0 base score of 2.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.

Key facts

Severity: Low (CVSS 2.0 base score 2.1)
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Microsoft Exchange Server
Published: 2001-10-30
Last modified: 2026-06-16

Description

Outlook Web Access (OWA) in Microsoft Exchange 2000 allows an authenticated user to cause a denial of service (CPU consumption) via a malformed OWA request for a deeply nested folder within the user's mailbox.

Frequently asked questions

What is CVE-2001-0666?: Outlook Web Access (OWA) in Microsoft Exchange 2000 allows an authenticated user to cause a denial of service (CPU consumption) via a malformed OWA request for a deeply nested folder within the user's mailbox.
How severe is CVE-2001-0666?: CVE-2001-0666 has a CVSS 2.0 base score of 2.1, rated low severity.
Is CVE-2001-0666 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2001-0666?: CVE-2001-0666 affects Microsoft Exchange Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2001-0666?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2001-0666 published?: CVE-2001-0666 was published on 2001-10-30 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:microsoft:exchange_server:2000:-:*:*:*:*:*:*

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